Collapsible treadmill

ABSTRACT

A collapsible treadmill is composed of a chassis having two support members in no contact with the ground; a main frame having an endless belt rotatable along a closed path; a folding device having a lifting frame, the lifting frame having two first lateral frames spaced from each other and two second lateral frames spaced from each other, the lifting frame having a rear end pivotably attached to the main frame and two active pivoting members formed at a front end thereof and contacting against the support members; two linking-up members having front ends connected with the active pivoting members and rear ends connected with the chassis; and two limiters mounted to the chassis and defining a limited space with the support members for limiting the space within which the active pivot members can act.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a treadmill, and moreparticularly, to a collapsible treadmill.

2. Description of the Related Art

To allow convenient storage of a treadmill, the commercially availabletreadmill is collapsible. For example, referring to FIGS. 1-2, aconventional collapsible treadmill 10 disclosed in U.S. Pat. No.5,674,453 is composed of a support structure 11 put on the ground, twoupright members 12 extending toward a top end thereof from the supportstructure 11, and a tread base 14 pivotably attached to respective innersides of the two upright members 12 via two base axes separately. Thetread base 14 includes a first section 14A and a second section 14Blocated reversely relative to the first section 14A.

When it is intended to collapse the tread base 14, apply an upward forceto the second section 14B to turn the first section 14A on the two baseaxes 13. In other words, the tread base 14 is moved upward to acollapsed position from an operational position. The treadmill 10 canthough function as collapsing the tread base 14, but it still has thefollowing drawbacks.

1. Where the tread base 14 is pivoted must be close to an end portion14C and there is none of any connecting member between the tread base 14and the support structure 11. When the tread base 14 is turned upward,an inertial force can be generated and applied to the upright members 12and the support structure 11, so the support structure is subject toshake.

2. When a user is jogging or running on the tread base 14, the wholeweight of the user and the tread base is supported by the two base axes13 to easily result in fatigue and deformation of the two base axes 13to further affect the long-term rotational and folding smoothness of thetread base 14.

Although Taiwan Pat. No. 1234471 disclosed an improvement on theaforesaid prior art, the improved structure has numerous components andit is complicated to assemble them, so the product cost is higher to beunfavorable to commercial competition, thus needing further improvement.

SUMMARY OF THE INVENTION

The primary objective of the present invention is to provide acollapsible treadmill, which platform is highly stable and which foldingstructure is simple and practicable.

The foregoing objective of the present invention is attained by thecollapsible treadmill composed of a chassis, two support members, astanding post, a main frame, a folding device, and two limiters. Thechassis includes two lateral bars spaced from each other and each havinga first end portion and a second end portion reversely located relativeto the first end portion. Each of the support members is mounted closeto the first end portion of one of the two lateral bars and does notcontact the ground. The standing post is connected to the chassis,extending toward the top end of the treadmill. The main frame includestwo lateral frames, a frame body, and an endless belt. The two lateralframes are spaced from each other and each have a first section and asecond section arranged reversely relative to the first section. Theframe body is formed of at least one fastening bar fixedly connectedbetween the two lateral frames. The endless belt is provided with two(front and rear) ends put inside the frame body for rotation along aclosed path. The folding device includes a lifting frame having twofirst lateral frames spaced from each other and two second lateralframes spaced from each other. A rear end of the lifting frame ispivotably attached to the main frame. The lifting frame has two activepivot members formed at a front end thereof and contacting against thetwo support members separately. Respective front ends of two linking-upmembers are connected with the active pivot members separately.Respective rear ends of the two linking-up members are connected withthe two lateral bars separately. The two limiters are mounted inside thechassis and define a limited space with the support members for limitingthe space within which the active pivot members can act.

Therefore, the platform of the present invention can be preferablystable and the folding structure of the same can be simple andpracticable because the lifting frame is mounted to the support membersvia the two active pivot members, the two linking-up members are mountedto the chassis, and the limiters have anti-run function.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the conventional treadmill underoperational status.

FIG. 2 is a side view of the conventional treadmill under collapsedstatus.

FIG. 3 is a perspective view of a first preferred embodiment of thepresent invention.

FIG. 4 is an exploded view of the first preferred embodiment of thepresent invention, in which the instrument unit is not shown.

FIG. 5 is a side view of the first preferred embodiment of the presentinvention, in which the instrument unit is not shown and one lateral barof the main frame is hidden.

FIG. 6 is similar to FIG. 5, illustrating that the treadmill ispartially collapsed.

FIG. 7 is similar to FIG. 5, illustrating that the treadmill is fullycollapsed.

FIG. 8 is another side view of the first preferred embodiment of thepresent invention, illustrating that the platform is being lifted.

FIG. 9 is similar to FIG. 8, illustrating that the platform is lifted.

FIG. 10 is a side view of a second preferred embodiment of the presentinvention.

FIG. 11 is similar to FIG. 10, illustrating that the treadmill ispartially collapsed.

FIG. 12 is similar to FIG. 10, illustrating that the treadmill is fullycollapsed.

FIG. 13 is another side view of the second preferred embodiment of thepresent invention, illustrating that the platform is being lifted.

FIG. 14 is similar to FIG. 13, illustrating that the platform is lifted.

FIG. 15 is a side view of a third preferred embodiment of the presentinvention, illustrating that the front ends of the linking-up membersare acentrically connected with the active pivot members.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

First of all, note that the relative positions, like “top” and “bottom”,set forth in the following paragraphs are defined based on the user'soperational orientation and identical or similar elements in differentpreferred embodiments are indicated by the same reference numerals.

Referring to FIGS. 3-4, a collapsible treadmill 2 constructed accordingto a first preferred embodiment of the present invention is composed ofa chassis 20 placed on a support surface (e.g. ground), a set ofstanding posts 30 mounted to a front end of the chassis 20 and extendingtoward a top end of the collapsible treadmill 2, a main frame 40connected with a platform 50, and a folding device 60 connected betweenthe chassis 20 and the main frame 40. The detailed descriptions andoperations of these elements as well as their interrelations are recitedin the respective paragraphs as follows.

The chassis 20 includes two lateral bars 21 spaced from each other, twoconnection bars 22 fixedly connected between the two lateral bars 21,and two support members 23 mounted to two lateral ends of the twoconnection bars 22 and close to the front end of the chassis 20. Thechassis 20 further includes conventional components at a rear endthereof, such as a pair of rollers 25, a hydraulic cylinder 26, and aretractable bar assembly 27. A receiving space is formed inside thechassis 20.

The standing post 30 includes a set of instrument units 32 mounted to atop end thereof.

The main frame 40 includes a front section extending into the receivingspace of the chassis 20 and connected with a platform 50. The main frame40 includes two lateral frames 41, each of which is formed of a firstsection 411 and a second 412 arranged reversely relative to and spacedfrom the first section 411, a frame body formed of three fastening bars42 fixedly connected between the two lateral frames 41, and an endlessbelt having a front end and a rear end, which are placed inside theframe body, and being rotatable along a closed path.

In practice, in the first preferred embodiment, an electric motor (notshown) is installed onto a front end of the main frame 40 for drivingrotation of the endless belt 44

The folding device 60 further includes a linear actuator 61, a liftingframe 63, two active pivot members 65, two linking-up members 67, andtwo limiters 70. The linear actuator 61 is mounted onto the main frame40 and has a lifting pipe 611, the length of which is retractable. Thelifting frame 63 is formed of two first lateral frames 631 spaced fromeach other, two second lateral frames 63 spaced from each other, and twofastening bars 633 fixedly connected between the second lateral frames632. The fastening bars 633 are connected with the lifting pipe 611 toenable the lifting frame 63 to be hauled by the lifting pipe 611 forelevation-angle lifting motion. The lifting frame 63 has a rear endpivotably attached to the main frame 40 and a front end thereofcontacting against the support member 23 via two active pivot members65. In this embodiment, each of the two active pivot members 65 is, butnot limited to, a wheel and a pivotal center on which the active pivotmembers 65 and the lifting frame 63 are connected protrudes from a frontend surface of the first section of the main frame 40.

Each of the two linking-up members 67 has a front end connectedcoaxially with one of the active pivot members 65 and a rear endconnected with one of the lateral bars 21. Each of the two limiters 70includes a combination portion 701 and a stop portion 702. Each of thestop portions is located on one of the active pivot members 65,extending forwardly and downwardly toward a front end of the treadmillslantingways.

Referring to FIGS. 5-7, when it is intended to collapse the main frame40 or the platform 50, the two active pivot members 65 can function asrespective folding points. The two active pivot members 65 are connectedwith the lifting frame 63 and hauled by the linking-up members 67 to thechassis 20, so the two active pivot members 65 will be confined withinthe support members 23 of the chassis 20 separately to be movable withinthe very small range. When the main frame 40 or the platform 50 pivotson the two active pivot members 65, the two active pivot members 65 maybe pulled upward by an inertial force; meanwhile, stopped by the twolimiters 70, the two active pivot members 65 can be prevented fromdisengagement from the support members 23 separately. Thus, the platform50 can be successfully collapsed.

Referring to FIGS. 8-9, when it is intended for the main frame 40 or theplatform 50 to lift the elevation angle, the linear actuator 61 canapply an upward force to the lifting frame 53 in such a way that the twoactive pivot members 65 are forced to contact against the supportmembers 23 and the counterforce will lift the front end of the mainframe 40 or the platform 50.

Referring to FIG. 10, a second preferred embodiment of the presentinvention is different from the first preferred embodiment of thepresent invention as recited thereinafter. A spacer 80 is furthermounted to a front section of the chassis 20 and a limiting member 85includes an upper end connected with the main frame 40. The limitingmember 85 is provided with an elongated slot 86 formed on a lowersection thereof and having an upper limit 861 and a lower limit 862 forlimited movement of the limiting member 85 along the elongated shot 86between the upper and lower limits 861 and 862. When it is intended tocollapse the main frame 40 or the platform 50, the two active pivotmembers 65 function as respective folding points. Connected with thelifting frame 63, the two active pivot members 65 are also hauled to thechassis 20, so the two active pivot members 65 are confined inside thesupport member 23 to be movable within the support member 23. Referringto FIGS. 11-12, when the main frame 40 or the platform 50 pivots on thetwo active pivot members 65; the two active pivot members 65 may thoughbe pulled upward but the lower limit is confined by the spacer 80 toprevent the two active pivot members 65 from disengaging from thesupport member 23 to successfully complete the folding operation. Inother words, the limiters 70 of the first embodiment have the anti-runfunction identical to that of the limiting member 85 of the secondembodiment, so if the present invention is actually manufactured, theset of the limiters and the active pivoting members or the set of thelimiting member and the spacer can be selectively adopted.

Referring to FIGS. 13-14, when it is intended to lift the elevationangle of the main frame 40 or the platform 50, the linear actuator 61applies a downward force to the lifting frame 63 and the two activepivot members 65 are forced to contact against the support member 23, sothe counterforce will lift the front end of the main frame 40 or of theplatform 50.

Referring to FIG. 15, in a third preferred embodiment of the presentinvention, the relationship of connection between the linking-up member67 and the active pivoting member 65 is interchangeable as recitedthereinafter. The front ends of the linking-up members 67 can beacentrically connected with the active pivoting members separately insuch a way that the active pivoting members 65 are movable forwardly andbackwardly for a small distance and thus the platform 50 can besuccessfully collapsed likewise.

In conclusion, the new-type lifting frame 63 of the folding device 60 ofthe present invention works with the two active pivoting members 65 andthe two linking-up members 67, which are mounted to the chassis 20, incoordination with the anti-run function of the limiter 70 or the spacer80 and the limiting member 85, so the platform 50 is structurally veryfirm and the folding device 60 thereof is structurally simple andpracticable.

Although the present invention has been described with respect tospecific preferred embodiments thereof, it is in no way limited to thespecifics of the illustrated structures but changes and modificationsmay be made within the scope of the appended claims.

What is claimed is:
 1. A collapsible treadmill comprising: a chassishaving two lateral bars and two support members, the two lateral barsbeing spaced from each other and each having a first end portion and asecond end portion arranged reversely relative to the first end portion,the two support members being mounted close to the first end portions ofthe two lateral bars respectively and having no contact with the ground;a standing post connected to the chassis and extending toward a top endof the treadmill; a main frame having two lateral frames, a frame body,and an endless belt, the two lateral frames being spaced from each otherand each having a first section and a second section arranged reverselyrelative to the first section, the frame body being formed of at leastone fastening bar fixedly connected between the two lateral frames, theendless belt having a front end and a rear end, which are placed insidethe frame body, for rotation along a closed path; and a folding devicehaving a lifting frame, two linking-up members, and two limiters, thelifting frame having two first lateral frames spaced from each other andtwo second lateral frames spaced from each other, the lifting framehaving a rear end pivotably attached to the main frame, two activepivoting members being mounted to a front end of the lifting frame andcontacting against the support members, each of the two linking-upmembers having a front end connected with one of the active pivotingmembers, each of the two linking-up members having a rear end connectedwith one of the lateral bars, the two limiters being mounted inside thechassis and defining a limited space with the support members forlimiting the space within which the active pivoting members can act. 2.The collapsible treadmill as defined in claim 1, wherein the chassiscomprises two connection bars fixedly connected between the two lateralbars; the two support members are mounted to two lateral ends of theconnection bars respectively and close to a front end of the chassis. 3.The collapsible treadmill as defined in claim 1, wherein each of the twolinking-up members comprises a front end coaxially connected with one ofthe active pivoting members and a rear end thereof connected with thetwo lateral bars of the chassis.
 4. The collapsible treadmill as definedin claim 1, wherein each of the two linking-up members comprises a frontend acentrically connected with the two active pivoting members and arear end thereof connected with the two lateral bars of the chassis, theactive pivoting members being movable forwardly and backwardly insidethe support members respectively when the platform is being collapsed.5. The collapsible treadmill as defined in claim 1, wherein each of thelimiters comprises a spacer and a limiting member, the limiting memberhaving an upper end connected with the main frame, an elongated slotformed on a lower section of the limiting member, the elongated slothaving an upper limit and a lower limit for limited movement of thespacer between the upper limit and the lower limit.
 6. The collapsibletreadmill as defined in claim 1, wherein each of the limiters comprisesa combination portion and a stop portion located above the activepivoting member.
 7. The collapsible treadmill as defined in claim 6,wherein each of the stop portions of the limiters is inclined forwardlyand downwardly toward a front end of the treadmill.
 8. The collapsibletreadmill as defined in claim 1, wherein a pivotal center on which theactive pivot members and the lifting frame are connected protrudes froma front end surface of the first section of the main frame.
 9. Thecollapsible treadmill as defined in claim 8, wherein each of the activepivoting members is a wheel.
 10. The collapsible treadmill as defined inclaim 1, wherein the folding device comprises a linear actuator mountedonto the main frame and having a lifting pipe, the length of which isretractable, the lifting pipe being connected with the lifting frame,the lifting frame being adapted for being hauled by the linear actuatorfor elevation-angle lifting motion.